Device for running in wires, etc., into tubular structures, in particular in concealed electrical installations



July 8, 195Z J. woLFF 2,602,845

DEVICE FOR RUNNING IN WIRES, ETC. INTO TUBULAR STRUCTURES, IN PARTICULAR IN CCNCEALED ELECTRICAL INSTALLATIONS 2 SHEETS-SHEET 1 Filed Aug. 19, 1950 l IN VFA/70E;

JOSEF Waar/C WM P J. WoLFF ab? o 1952 DEVICE FCR RUNNING IN WIRES, ETC., INT0 TUBULARZGOZ845 STRUCTURES, IN PARTICULAR IN CCNCEALED ELECTRICAL INSTALLATIONS Filed Aug. 19, 1950 2 SHEETS-SHEET 2 Patented July 8, 1952 DEVICE FOR RUNNING IN WIRES, ETC., INTO TUBULAR STRUCTURES, .IN PARTICULAR IN CONCEALED ELECTRICAL INSTALLA- TIONS Josef Wol, Zurich, Switzerland, assignor to A.

Brunschweiler & Co., Metallwarenfabrik, Kusnacht-Zurich, Switzerland Application August 19, 195o, serial No. 180,362

In Switzerland August 26, 1949 (Cl. F75-376) 4 `Claims.

Hitherto it has been the practice to draw in the electric wires in concealed wiring installations by pushing a exible rod through the tube structure by hand and afterwards to alix the wires to be drawn in to its end so that on said rod being withdrawn said wires could be run into the vtube structure. The insertion of the flexible rod was a tedious work since due to its necessary thinness and the flexibility required the rod was very difficult to be gripped.

This diiiiculty is to be eliminated by the present invention. It relates to a device having a flexible rod insertable in the tube structure for the subsequent securing and drawing-in of the wires etc. and is characterized by comprising two tubes fitting into each other for longitudinal displacement the outer of which serving as a handgrip and by the inner of which the flexible rod is displaceable by said inner tube having secured to it a clamping device with at least one movable jaw, said movable jawv being in its turn in connection with a second hand-grip in such a manner that on displacing said inner tube by means of said second hand-grip in one direction said clamping jaw comes to bear against said flexible rod and moves it along, whereas on displacement in the other direction said clamping jaw releases said flexible shaft so that said inner tube carries out an idle return movement.

The accompanying drawings illustrate various examples of construction of the object of the present invention wherein;

Fig. 1 shows a rst example of embodiment of the device in side elevation,

Fig. 2 is a front view thereof,

' Fig. 3 is a partial longitudinal section thereof seen from the side,

Fig. 4 shows an alternative example of embodimentof the device partially in longitudinal section seen from the side, Y

Fig. 5 is an elevation viewed in the direction of the arrow V in Fig. 4,

Fig. 6 illustrates a third example of embodiment of the device in longitudinal section,

Fig. 7 shows the device according to a fourth example of embodiment in side elevation,

Fig. 8 is a detail of Fig. '7 in longitudinal section,

Fig. 9 shows a partial cross-section along line IX--IX in Fig. 8.

The device illustrated in Fig. 1 to 3 has two tubes I and 2 fitted in each other for longitudinal displacement the outer I of which serves as a hand-grip and by the inner 2 of which the flexible rod 3 is displaceable. At one end of theouter tube I serving asa hand-grip a tube-shaped extension 4 preferably adapted flexibly is provided, said extension being partly inserted into the tube structure into which subsequently the wires etc. are to be run in. At the other end of said handgrip the inner tube 2 (termed hereinafter the first tube) projects to a certain extent out of said hand-grip, said inner tube being rigidly connected to two annular disks 5 secured tothe wall of said tube and arranged parallel to each other. Said two disks form the supporting member for the two clamping jaws 6 extending into the interstice between the two annular rings and being pivotally mounted at their centre at two points of the annular rings 5 disposed opposite to each other by means of the pins 'I. The pins' Veach extend through an oblong hole 8 (Fig. 3) of the clampingjaws. One end of the `clamping jaws 6 takes the form of a saddle-shaped androughened clamping surface coacting with the flexible rod 3, whereas the other end of the clamping jaws is pivotally mounted on a pin I0 each between two essentially semi-circular carrying members 9. The carrying members 9 are rigidly secured to one end vof a second tubular-shaped hand grip II (termed hereinafter the second tube) surrounding the flexible rod 3 concentrically and arranged in the same plane as the tubes I and 2. As will be seen from the drawings', the rst tube 2- and the second tube II define a gap arranged at one end of the second tube I I and being adapted to accommodate part of the flexible member or rod 3. The jaws 6 project into said gap- The outer tube I is provided with an opening I2 near its front end through which the flexible rod 3 can be securely held by means of a linger, by way of example by the thumb of the hand gripping the hand-grip I. A ferrule I3 is slideably arranged on thetube I and is adjustable by means of a screw I 4 and has a projection I5 which can be brought to bear against a fixed point when working with the device.

On using the device described first of all one end of the flexible rod 3 is pushed through the second hand-grip I I and through the inner tube 2 and is then inserted in the tube structure into which subsequently the wires, such as electric conductor wires, are to be run in. The exible extension 4 on the tubular-shaped hand-grip I is also partly inserted in the tube structure. Then the tubular-shaped hand-grip I is gripped with one hand and held securely, whilst the other hand grips the .second hand-grip II and with the help of said second hand-grip pushes the tube 2 into the outer tube I serving as a hand-grip. At the same time a relative displacement of the hand-grip II in the axial direction towards the inner tube 2 takes place so that the lever-shaped clamping jaws 6 carry out a pivoting movement in radial planes lying in the longitudinal axis of the device and are brought into the position shown in Figs. l and 3 and thus clamp the flexible rod 2 securely in between. On pushing the inner tube 2 forward the flexible rod 3 is thus carried along by the clamping jaws 6. After fully inserting the inner tube in the hand-grip I, the second hand-grip II is again drawn back in the other direction, a relative pushing apart of the parts 2 and II first of all taking place causing the clamping jaws 6 to be pivoted into the position shown by broken lines in Fig. 3. The clamping surface of the jaws are thereby disengaged from the flexible rod 3 and thus release it so that the inner tube 3 carries out an idle return movement. During the return movement of the second hand-grip II the flexible rod 3 is with advantage held tight through the opening I2 of the outer tube I thus to prevent the rod 3-from sliding back until the clamping device has opened.

Afterwards the inner tube 2 is again pushed into the tube I by means of the hand-grip I I, the flexible rod 3 thereby being pushed into the tube structure by a further amount. This procedure isv again and again repeated until the end of the flexible rod 3 appears at the other end of the tube structure whereupon the wires to be run in are aihxed to said end of the rod 3 and are run into the tube structure by pulling back the flexible rod.

On the relative pushing together of the second hand-'grip II and the inner tube 2 the annular rings 5 forming the supporting part of the clamping jaws. 6 abut against the supporting parts 8 when the clamping jaws 6 attain the position of maximum clamping action so that they are not opened again by pivoting beyond this position.

The construction shown in Figs. 4 and 5 differs from the example of embodiment described above in-that the support parts 9 are adapted as complete rings to which a guiding sleeve IIil surrounding the tube 2 is rigidly secured. This measure has the advantage that the second hand-grip I I is guided coaxially to the first hand-grip in an axial direction whereby a buckling of the flexible rod between the tube 2 and the hand-grip II is altogether eliminated.

In the example of embodiment of the object of the present invention shown in Fig. 6 the inner tube 2 is in rigid connection with the second hand-grip II by the tube 2 being completely passed through the longitudinal bore of this handgrip and by being anchored therein. Between the first' hand-grip I and thesecond hand-grip II a housing I'I for the clamping device is rigidly secured to the inner tube 2. A- clamping jaw 6 is pivotally arranged in the housing I'I and can coact with the flexible rod 3 throughan opening in the tube 2 by means of one of its ends adapted as a clamping surface. A spring I8- engages the clamping jaw with one end and the hand-grip II with the other end and has the tendency at all times to bring the clampingl jawe into contact with the flexible rod 3-in ordento clamp said rod 3 between the clamping jaw and thewallof the tube 2. A rearward extension I9 offthe clamping jaw 6 can be manipulated from without, asis shown in Fig. 6. Thus it is possible to pivot the against the action of the spring I8.

The method of operation of this device is similar to that described for the rst example. On pushing the inner tube 2 into the outer tube I serving as a hand-grip by means of the second hand-grip I I the flexible rod 3 is carried along by the clamping jaw 6, the clamping action first of all being initiated by the spring I8 and afterwards increased during the advancing of the hand-grip II by the jamming action due to the position of the clamping jaw 6 shown. After fully inserting the inner tube 2 into the tubular grid I the second hand-grip I I is again withdrawn in the other direction, whilst the flexible rod 3 is held tightly through the opening I2 of the tube I not shown. During this operation the clamping jaw 6 pivots against the action of the spring I8 in such a manner that the rod 3 is released so that the tube 2 can carry out an idle return movement. In case of need the clamping jaw 6 can be released at every return movement of the handgrip I I by means of a finger of the hand gripping this hand-grip.

The example of embodiment shown in Figs. 'I to 9 is an alternative execution of the embodiment just described. Between the inner tube 2 and the second hand-grip II there is a box-shaped housing I1 connecting the two parts 2 and II rigidly with each other. In addition the housing I1 serves as a support for two clamping jaws 6 located within said housing, said clamping jaws being pivotally mounted by means of the screws I0 in a plane lying in the longitudinal axis of the device. The ends of the clamping jaws facing each other are again provided with saddleshaped and roughened clamping surfaces between which the flexible rod 3 can be clamped. From Fig. 8 it is evident that the clamping surfaces are adapted in such a manner that the jaws can be pivoted from the horizontal position of maximum clamping action as shown with full lines upwardly into the position shown with broken lines in order to release the rod 3,l whilstv on the other hand a pivoting of the jaws beyond their position for maximum clamping action in the other direction is impossible due to reciprocal locking. Each clamping jaw 6 carries a projection I9'V formedby a screw projecting outwardly through an associated opening 20 of the lid Ila of the housing. A rod-shaped spring I8 is held at its two ends in recesses of the clamping jaws i and has the tendency at all times to pivot said jaws into the position of maximum clamping action. i

The method of use of thedescribed device is the same as with the example accordingto Fig. 6. If for any reason the clamping jaws 6 are to release the flexible rod 3, the jaws can be pivoted against the-action of the lspringlil'by displacing the lp'rojections I9 projecting. out of the housing y The device according to the'present invention has the advantage that the running in` of the fiexible rod intoany tubular structure can-be carried out Without trouble and at'the same time eliminating any danger-'of damaging the rodby buckling etc. In particular with' thelexample of embodiment according to Figs. 4 to 9 a buckling ofv the flexible rod in the clamping, device/even with awkward manipulation of the device is quite impossible because; thetwoy hand-grips I and II areguided co-axially to eachother. /With this guiding action ofthe two hand-grips a smoother anded more certain operation of the device isassur y.

What we wish to claim and secure by Letters Patent is:

1. A tool for moving a flexible Vmember through a conduit, comprising in combination, a first tube; a second tube arranged in alignment to said first tube, said rst tube and said second tube defining a gap arranged at one end of said second tube and being adapted to accommodate part of the flexible member so that the same bridges said gap; a member rigidly connected to the end of said second tube adjoining said gap; a pair of jaws arranged oppositely lto each other and pivoted at the ends turned away from each other to said member, said jaws projecting into said gap so as to clamp the flexible member in position with respect to said second tube; and means for holding said jaws in clamping position when said second tube is moved longitudinally in one direction with respect to the conduit and for releasing said jaws from the clamping position when said second tube is moved longitudinally in the opposite direction with respect to the conduit.

2. A tool as claimed in claim 1, said holding and releasing means comprising a ring-shaped member rigidly connected to said first tube and having two slots arranged on opposite sides thereof, and pins rigidly connected, respectively, to said jaws and engaging, respectively, said slots,

6 said ring-shaped member abutting against said member rigidly connected to said second tube.

3. A tool as claimed in claim 2, said member rigidly connected to said second tube having an annular shape so as to enclose said ring-shaped member; and a sleeve rigidly connected to saidA JOSEF WOLFF.

REFERENCES CITED The following references are of record inthe file of this patent:

UNITED STATES PATENTS Number Name Date 1,880,431 Goodall Oct. 4, 1932 Mistelsk May 22, 1934-. 

